Thread by @rising_serpent

1. The only way to end the pandemic is through, not around it.
We were supposed to flatten the curve in 21 days. Fast forward 213 days and we're still talking about lockdowns, mask mandates and school and business closures and virus spikes.

2. If lockdowns worked, we wouldn't be where we're today. If masks were the silver bullet panacea they are being made out to be, we would have flattened the curve right after Fauci, CDC and the surgeon General changed their minds and insisted all of us begin using them.

3. In fact in one CDC case series majority of people getting infected wore masks all the time.
To be clear, I'm not saying they have zero efficacy, I'm saying they're not likely to make a significant impact on disease incidence, because their efficacy is at at best mild.

4. Similarly, statistics from New York City showed that majority of people getting infected were actually locked down at home. Again, it doesn't mean you should go out and lick door knobs, it just means lockdowns aren't effective as a public health measure.

5. The biggest predictor of proclivity to infection is the number of actively infected people in the local community, which is also a reflection of communal herd immunity.
Places that had high previous infections, won't be affected nearly as severely in the so-called second wave

6. And the number of infected people in the local community is directly proportional to population density. Sparsely populated rural communities are less affected than urban concrete jungles with high rates of public transport usage.

7. The other interesting part is the declining mortality. Some of this is directly related to the number of tests being performed, increasing the denominator (total cases). But other factors must be considered.

8. Viruses routinely undergo attenuation during epidemics via "serial passage through the host"
There's also a possibility that the most vulnerable population was the first to die. We're also a whole lot better at treating it than when it all began.

9. There's also the whole nebulous and poorly defined "herd immunity" question.
At a specific communal threshold, having a certain percentage of the population immune to a disease protects from disease uninfected individuals.

10. This is the bedrock of vaccination as a public health measure. It's why we don't see measles in communities with a large number of vaccinated individuals.

11. The problem with Coronavirus is that no group of experts has come to a reasonable conclusion as to what percentage of immune individuals in the community constitutes herd immunity. Some say 60%, others think as low as 20% should suffice.

12. Also, it's no longer a matter of speculation. Reinfection after natural infection does occur, very rarely, so far. Which means immunity after natural infection is not 100%. At the same time this is not likely to be a major factor can herd immunity.

13. The duration and degree of protection after natural immunity remains a matter of speculation, some studies put it at as little as 4 months, others say it lasts for years.
A second infection is likely to be much milder than the first one. But it can happen.

14. It follows logic then that the vaccine will not confer 100% immunity either. Just how much it will won't be known for a long time. Vaccine efficacy studies don't require 100% efficacy, they require more efficacy than a comparator/ placebo or in this case, the unvaccinated.

15. So, if the rate of infection in the unvaccinated is x% and that in those vaccinated is y% and as long as the difference is statistically significant in favor of the vaccine, it establishes efficacy.

16. The point here is that no single intervention has yet been proven to effectively extinguish the epidemic. We have 6 months worth of data to say this with some degree of certitude.

17. Coronavirus testing is another conundrum. The positive predictive value of a test is directly related to the pre-test probability of the disease.
Which means the likelihood that a positive test is a true positive goes up when done on those with the right signs and symptoms.

18. Which also means that the false positive rate goes up when you do it in a lot of people that are completely asymptomatic.
See where I'm going with this here?

19. In the US most tests are reported as a binary positive or negative. Which means that if the test detects any amplification signal, it results as a positive.
In many other countries they report let us called a "cycle threshold"

20. A PCR test takes several cycles to amplify viral genetic material. The exact cycle during which the test turns positive is called the cycle threshold.
The higher the cycle threshold means the less amount of genetic material there is and more cycles needed to amplify it.

21. This also means that the higher the cycle threshold the lower the viral load.
We don't routinely get this information in the United States.
Is more likely than not that the false positives occur at very high cycle thresholds or barely amplifiable genetic matter.

22. We really don't know how many of the so-called asymptomatic cases where false positives and at what cycle threshold their test turned positive. This is more pronounced with unrestricted freely available testing and totally asymptomatic individuals getting tested on demand.

23. Maybe it is time to routinely report out cycle thresholds and reconsider positive diagnoses in totally asymptomatic individuals with very high cycle threshold numbers.

24. Doing more of the same hasn't really worked. In fact some of the countries with the strictest lockdown rules and mask mandates aren't doing any different or better than those that never implemented them.
At what point do we say "this isn't working?"

25. The only thing we've done well is to clutch at the talisman of draconian measures and fervently wish it'll all go away while pointing fingers at people who don't conform to 6 months worth of hocus pocus masquerading as evidence that was never really there.